Generally speaking, "走" means "walk". But in some phrases, we use other words to express different meanings. For example. "……,when I walk on the road." 当我在路上走的时候……(Emphasize the action)
"I walk to school."我走路去学校。(Emphasize the fashion)"I prefer taking a walk after dinner."我喜欢饭后散步。(Emphasize relaxing)"walk around" 四处走走 (Two-syllable words emphasize relaxed action easy done)